Clinical experience shows that newly-fit hearing-impaired persons often report that their devices are too powerful, especially in the higher frequencies. This result is not completely unexpected, because to the sensor in a neural-impaired ear, the increased audibility of softer, especially higher frequency sounds may be unsettling during the first few weeks of use. This newly audible information may be disturbing not only for first-time users, but also for experienced users accustomed to devices with less HF gain, or users who have worn only one instrument previously and now are being fitted with two.
Typically, a fitting system (an adaptation manager) for a hearing device, e.g. a hearing aid, is configured to allow first time users to adapt to the increased sound level (provided by the hearing device) by slowly turning up gain over time. So the first time user gets less gain (more compression) at the first fitting (than an experienced user with the same hearing loss profile) and will typically after an adaptation period, of e.g. 2-3 months use, get the prescribed gain as e.g. determined by a user's hearing profile (e.g. an audiogram) and a fitting algorithm (fitting rationale, e.g. NAL, DSL, etc.) translating hearing loss versus frequency to prescribed gain versus frequency for a specific hearing device.
The problem is that the rest of the hearing aid feature set (e.g. directionality and noise reduction, etc.) is not necessarily included in the ‘first time user fitting strategy’ of the fitting system. A cost of the lowering of gain (in particular of the lowering of gain at higher frequencies (e.g. above 2 kHz)) is that speech intelligibility is less than optimal.